How to italicize text in a selected rows in one column in table using kable?

Question

I am trying to make a report in a LaTeX format using R. The file format is in .Rnw. I am preparing a table using the kable and kableExtra packages but I have only one problem.

Here's the screenshot of the table I made:

I wanted to make the two species (in rows 1 and 2 of column 1) to be in italics. How to make it?

Thanks.

Here's the data:

df1 <- data.frame(`Species Name` = c("Encrasicholina punctifer", "Stolephorus indicus", "Others", "Total"),
                  `2014` = c(171.12, 0, 0.59, 171.72),
                  `2015` = c(231.18, 3.07, 0.29, 234.55),
                  `2016` = c(412.1, 0, 0.44, 412.54),
                  Total = c(814.4, 3.07, 1.33, 818.8),
                  Percent = c(99.46, 0.38, 0.16, 100))

By the way, here's the R code:

\begin{table}[H]
\centering
<<table_2>>=
df1 %>% 
  kable(format = "latex", 
        booktabs = T) %>%
  kable_styling(latex_options = c("HOLD_position"),
                position = "center",
                font_size = 9) %>% 
  row_spec(0, bold = T) %>% 
  row_spec(4, bold = T)
@
\end{table}

Answer 1

kableExtra comes with a function cell_spec which can be used to add extra styling to the table. However, in comparison to kable_styling, this has to be used before the kable function is called. This is explained within the guidance here: https://haozhu233.github.io/kableExtra/awesome_table_in_pdf.pdf

However, if you only want to edit a few individual cells, I find it is better to just reformat the data manually. As seen in this similar question, you can change the cell name to \textit{YOUR STRING}* to make the words italics.

I wasn't able to get your Rnw file working, so here is a fully reproducible Rmarkdown .Rmd file. The only difference to the .Rnw file in principle is that you need to add a double backslash to the formatting of the LaTeX command to make sure they are read by pandoc (i.e. \\textit{}):

---
output: pdf_document
---

```{r}
df1 <- data.frame(`Species Name` = c("Encrasicholina punctifer", "\\textit{Stolephorus indicus}", "*Others*", "\\textbf{Total}"),
                  `2014` = c(171.12, 0, 0.59, 171.72),
                  `2015` = c(231.18, 3.07, 0.29, 234.55),
                  `2016` = c(412.1, 0, 0.44, 412.54),
                  Total = c(814.4, 3.07, 1.33, 818.8),
                  Percent = c(99.46, 0.38, 0.16, 100))
```


```{r}
knitr::kable(df1)
```

Note: I would recommend the use of RMarkdown over .Rnw. You can fully customise the LaTeX template just as you do with the Rnw file, and it is much more supported. Sweave was dropped by the author over 5 years ago: https://yihui.name/knitr/demo/sweave/